Flexible driving connection for tool holders



Nov. 25, 1930.. B. R SCHILTZ 1,782,633

' FLEXIBLE mums comwc'rxon FOR TOOL nommns Filed A ril 27, 1926 2 Sheets-Sheet 1 ddb'c a e b f INVENTOR, BERMRD P scrum-m,

ATTORNEY.

Nov. 25, 1930.

B. P. SCHILTZ FLEXIBLE DRIVING CONNECTION FOR TOOL'HOLDERS 2 Sheds-Sheet 2 Filed April 27, 1926 INVENTOR .BE-RNARD P. scruL'rzQ,

BY l

' ATTORNEY.

FKia-T- in s I have employed the "same character of Patented Nov. 25, 1930 um'reo STATES Y BERNARD P. SCHILTZ,

or CLEVELAND, c1110 rpnxrnnn nmv'me connnc'rion FOR 'roon nonnnns Application filed April '27,

My invention relates to improvements in flexible driving connection for tool holders especially adapted for actuating taps, drills,

1926. Serial no. 1o4,eo 2.

I As connecting means v for the members of my flexible driving connection, there are provided two sets of steel balls, each divided into a and the like, and has forits Object the provigroups of -.two, as b'--b, d b b th sion of rotating or drivingmeans whereby groups being disposed in four adjacent the rotated member, reamer,or tap shall be, planes, as indicated in Figs. land 2, of which i afforded a considerable range of automatic hand. The requirements involve the 'proviand convex faces accommodation to the particular work in the sectioned portions arerespectively at right angles. A ball cage having concave '0 a", is adapted to accomsion of a compact driving connection having modate thefirst set of steel balls b b", the

a-wide range of adaptation and use, consisting of parts essentially simple in construction, while afi'ordinglong wearing qualities. The

desired flexibility, moreover, does not admit.

groups thereof being disposed in diametrically arranged openings so that the first group b will extend within the diametrical groove (1 provided in the bottom face of block a.

of loose connections or lost motion, and the The Second g p of balls in turn, extend flexible driving connection must beone adapted for use by the average mechanic. Having thesequalities and requirements in mind, I

have developed the compact, simple and re1a.-.

- after described indetail and shown in the acshank a is connected with a power-drive companying drawings, wherein:

' my improved flexible driving connection;

' Fig. 2 is a'view thereof in elevation, broken away midway and insection, in order to illustrate the flexible drivingvmenibers;

Fig. 3 i'sa transverse section on line 3-3,

1; ig. 4 is another section on line 4-4, Fig. 1;

- Fig. 5 is a section through the chuck on line 55, Fig. 1, and e N V Fig. 6 is a fragmentary view of a multiplespindle tapping mechanism employing three -of my improved driving connections in exaggerated showing of various capacltles for adaptation to the conditions. of the work bemg done. Fig. 7 is a large assembly view.

Throughout the several figures of the drawre erence to indicate similar parts. a

It will be understoodthat the broken rotation of my improved connection and any inserted tool. This shank has an integral threaded block a resentin .a hollowed spherical face a. I t is axia y bored at at and radially bored at a, (Fig, 3) three openings of two diameters each bemg provided t 120 displacement.

away for within the groove 03' of a spherical faced member 03 havlng a centering opposing extension cl" extending within the bore a beyond the connectmg means. It will be observed that 20 ti l inexpensive d i connection h f inthe respective concave and convex faces of theseengaging members a, 0 and d have the same curvature so that they will fit closely together and afford free relative concentric movement, except as restricted by the overlapping or entering bodies of the'steel balls. These assembled members form essentially a 7 ball and socket driving connection.

The bottom of member d is plane-faced and is provided with a diametrical groove (i at I right angles to d, wherein the first group b of the second set of balls extend, being main-' tainedin position by the disc-like ball cage 0 interposed between the members (1 and f. Within the openings provided-in cage e, the other group of balls bf are positioned to ex tend within the diametrical groove f 'provided upon the inner face of member f. The latter is shouldered at f to accommodate the spacing ring g. beveled at its lower edge and all of the driving connections are assembled in operativeirelation by means of the enclosing casing giwhich screws upon the exteriorly threaded block a; c .As 'best indicated in Fig. 3, the centering stem d of member d is engaged by the three studs '5, tensioned by-theirrespective springs a", normaly to maintain said stem andthe associated members of the driving connection in axial alinement with the shank a; This isthe normal driving position wherein the special features of my' flexible mounting are afforded no unusual function beyond driving the inserted tap j, held Within the socket f by means of the ball 9" and its coacting ring j. The resilient centering or alining means, however, afi'ord the important function of accurately presenting the tool or group of tools to the work, as particularly demanded with automatically operated machines.

From a consideration of the structural features of the driving parts, however, it will be appreciated that the several members respectively have suflicient play upon one another in their assembled casing so that both lateral and axial displacement of the tap or inserted tool and its angular movement are readily obtainable without affecting its driv ing relation in any way.

Referring particularly to Fig. 7, it will be seen that the upper set of balls and their associated interconnected members afford, a

wide angular displacement of the tap with respect to the axis of its driving shank. Of course, the connecting parts are well oiled and these play upon one another while rigidly connected for rotation by the balls, so that the tap may be driven at an angle to conform with faulty working conditions, without danger of damage to the parts. In effect, the upper set of balls and associated elements provide a universal joint, compensating for a material angular displacement of the tap; having also the functionsof a ball-bearing. One advantageous employment of this feature or capacity of my improved device is 1nd1cated in Fig. 6, illustrating the use of three flexible driving connections in aimultiple-spindle tapping mechanism. The two outer taps are shown to be operating in holes drilled in the work is at different angles. The middle spindle is shown to be operated upon a hole that is laterally displaced to the left with respect to the regular spacingof the openings to be tapped. This irregularity, however, is compensated for by the lower set of balls and their driving connections, which permit the offset rotation .of the tap with respect to the axis'of the driving shank. Of course, these illustrations are not intended to represent working conditions, but their exaggeration will serve to make clear the-func-v tions and advantages of my instant improvement.

Although I have employed the multiplespindle tapping mechanism just explained and shown in a fragmentary way in the drawings, it should be understood that my invention is not restricted to the particular mechanism, taps, or other devices explained herein by way of illustration. My invention, in-

stead, relates to and comprises a flexible drivng mechanism having the capacity for rotating an associated element in offset relation or in angular axial relation, or both, to the end that mechanical irregularities in the work 1,7a2,ess

are compensated or automatically accommodated in accordance with the principles indicated above. l

The provision of two associated sets of balls, which within the apertured or socketed openings of the respective ball cages afford co-acting universal joint connections, likewise affords a substantially frictionless automatic adjustment of the several parts. This is of importance for the reason that the tap, reamer, or other tool must operate under considerable downward pressure and torque, so that the ready adjustment of the several members is practically an essential requirement herein.

It will be seen that either set of the ball and socket members of my improved driving connection may be brought independently into action according to the conditions of the work being done. Thus, the upper universal joint permits the free angular adjustment of the tool, within certain limits, while the lower ball and socket connection permits the tool to float or accommodate mere axial displacement. also within certain workable limits. All this is accomplished, because of the ball and socket connection of the driving members, without appreciable wear or friction. v

Having now described the preferred embodiment of my invention, I claim as new and desire to secure by'Letters Patent, the following:

1. In a device of the class described, the combination with a driving and an associated driven member, of interposed connecting means comprising members having coactmg convex and concave spherical faces adapted freely to turn concentrically upon one another, and interconnecting balls associated therewith for rotatably uniting said members, together with plane-faced connecting members and interconnecting balls permitting offset rotatable movement of the parts,

substantially as set forth.

2. In a device of the classdescribed, the combination with a driving and an associated driven member including a tool-holder, of

interposed connecting means comprising faces with an interposed ball cage of concavoconvex form, all adapted freely to tum con I centrically upon one another, interconnecting balls associated therewith jot-rotatably 5 uniting said members, and resilient alinin means acting upon the opposing extension 0 said tool-holder, substantially as set ,forth.

In testimony whereof I 0 now aflix my signature. e m BERNARD P. SCHILTZ. 

